Land mobile radio (LMR) systems are wireless communications systems that typically include at least one base station and a plurality of mobile terminals, where the plurality of mobile terminals are able to communicate with each other by the at least one base station. Often a network of interconnected base stations is used to connect mobile terminals across a large geographical area.
LMR is popular for military, law enforcement and emergency response applications, and is also popular with certain commercial entities, as it provides an efficient means of communication to a large number of users. Modern LMR systems involve trunked radio communication. In trunked radio systems, a pool of channels is centrally maintained, and channels are allocated dynamically to groups of users, when required. Trunked radio systems are more efficient than systems that provide static channel allocations, as resources can be shared among groups of users as needed.
A problem with trunked radio LMR systems of the prior art is that a number of useable channels is inherently limited. When all channels are allocated, any further communication requests are either denied or queued until channels become available again.
Attempts have been made to utilize other communications systems together with LMR. These attempts have included providing push-to-talk (PTT) functionality using alternative broadband data communication networks. In certain systems, the PTT functionality is linked to the LMR network, perhaps via the Internet, enabling LMR and PTT devices to communicate with each other.
However, a problem with combining LMR and broadband PTT functionality using alternative data communication networks is that network resources may not be used efficiently. For example, a user may interact with an LMR channel using both an LMR device and a mobile broadband device including PTT functionality, which can be both distracting and inefficient. Similarly, some users may interact using LMR, whereas others interact using broadband PTT, which can result in an increase in resource utilization as both LMR and broadband PTT resources are required.
Accordingly, there is a need for an improved trunked radio communication system and method.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.